The present invention relates generally to optical waveguides, and, more specifically, to optical panels formed therefrom.
U.S. Pat. No. 5,381,502 discloses a polyplanar optical display (POD) including ribbon optical waveguides laminated together. Image light is projected through an inlet face of the display for total internal reflection therein, with a video image being displayed at an opposite outlet face end of the panel.
U.S. Pat. No. 5,455,882 discloses another form of a POD panel configured for interactive operation. The video image is projected outbound through the stacked waveguides, and an interactive light beam may be directed inbound through the outlet face toward the inlet face for detection of its screen position for providing interactive capability.
In both patents, the similarly configured optical panels permit light transmission in either direction from the inlet face to the opposite outlet face, or from the outlet face to the opposite inlet face. This capability permits the use of the optical panels in various applications for providing high definition viewing screens for televisions, computer monitors, and various other types of viewing screens as desired.
Typically, detection of the inbound light for interactive capability may be effected using a conventional linear array of photodiodes. The array is sized in length to bridge the entire stack of waveguides for detecting inbound light in each waveguide for determining the corresponding position thereof. However, the cost of the array increases with the required total length thereof, and correspondingly increases the associated cost of the optical display which is a significant factor in competitive marketing thereof.
Furthermore, another advantage of the POD panels is their relative light weight notwithstanding the relatively large sizes in which they may be made. A panel having a diagonal measure of one to two meters, for example, has a correspondingly large viewing screen over which a correspondingly large area of interactive capability may be effected. Detecting inbound light for interactive capability typically requires correspondingly long arrays of photodiodes for effectively covering the entire viewing screen.
Accordingly, it is desired to provide a display system having interactive capability with corresponding advantages in implementation.